Introduction
The eyelids have two lamellae – an anterior lamella of skin and orbicularis muscle and a posterior lamella of tarsal plate and conjunctiva.
Partial-thickness defects of the lid or periocular region require reconstruction of only the anterior covering layer. This is achieved with a skin graft (separated from its blood supply) or a skin flap (with its blood supply intact).
Full-thickness eyelid defects require the reconstruction of the posterior lining layer ( Ch. 16 ) as well as the anterior covering layer. When both of these layers have to be reconstructed at least one of them must have a blood supply. This means combining an anterior (skin) flap with a posterior graft, or an anterior (skin) graft with a posterior flap. Alternatively, both may be flaps. A free graft placed on another free graft will fail.
The reconstructed lid needs support at both ends. This is particularly true in the lower lid. If either canthal tendon has been disrupted it must be reconstructed to restore attachment to the normal anchor points on the orbital rim – the posterior lacrimal crest medially and the lateral orbital rim, in the region of Whitnall’s tubercle, laterally.
In planning the method of reconstruction avoid excess tension or distortion. Design the flap so that any tension is parallel to the lid margins – horizontal rather than vertical. Try to match a skin graft colour accurately with careful choice of the donor site.
The techniques described in this chapter may be used alone to reconstruct the anterior covering lamella in partial-thickness defects of the periocular region, or within the lids if the posterior lamella is intact. They may also be used in combination with techniques described in Ch. 16 to reconstruct both lamellae in full-thickness lid defects.
Classification
Skin grafts
full thickness
split thickness
Skin flaps
advancement
rotation
transposition
Use of skin grafts to fill the defect
Unlike most skin flaps, where some tension is inevitable, skin grafts fill a defect with no residual tension. The risk of distortion of the lid margin is therefore minimal providing the graft is of adequate size.
A skin graft must be placed on vascularised tissue. See Ch. 2 , Sect. C , p. 37 for donor sites, techniques of fixation of grafts and their complications.
Choice of operation
In the preseptal area of the upper lid thin skin is required. This should be full-thickness skin from the opposite upper lid if possible, or a split skin graft for larger defects. The best colour match is eyelid skin.
15.1
Full-thickness graft to partial-thickness defect – lower lid
Full-thickness grafts contract very little and are preferable to split-thickness grafts whenever possible. The colour match and mobility are also superior.
Excise the area to a depth sufficient to clear the lesion. Make a template of the area and prepare a suitable graft (see 2.8–2.10 ). Upper lid skin is ideal for the upper or lower lids, if available.
15.2
Full-thickness graft to partial-thickness defect – upper lid
Place the graft and fix it with a bolster (see Figs 2.12a , b , 15.4b , c ) because the upper lid is more mobile than the lower lid. Quilting sutures are an alternative method of fixation (2.14).
15.3
Full-thickness graft to inner canthus
Defects superior to the medial canthal tendon may be reconstructed with a glabellar or other local skin flap (15.13–15.15). Inferior to the tendon a skin graft is usually preferable.
15.4
Split-thickness graft to partial-thickness defect
Split-thickness grafts contract more than full-thickness grafts but for larger eyelid defects, particularly in the upper lid, they are preferable if insufficient skin is available from the opposite upper lid, in which case alternative donor sites have to be considered.
Excise the lesion and harvest a split skin graft of suitable size (see 2.11 ). Suture the graft into the defect without tension, allowing a small overcorrection to compensate for later contraction.
Use of flaps to cover the defect
Skin flaps used to reconstruct the periocular tissues are almost always local flaps with a random pattern blood supply. Flaps with an axial pattern blood supply are used occasionally. The general rule that random pattern flaps should have a length/breadth ratio of 1 : 1 can be relaxed in reconstruction of the face because of the rich blood supply compared with the skin of the trunk or limbs. Because skin flaps have an intact blood supply it is not essential for the posterior lamella to be vascularised (see Introduction to Chs 15 and 16 ). Skin flaps are undermined within the layer superficial to the facial muscles (usually the subcutaneous fat or fascia) to allow movement to their new site with a minimum of tension. If the skin is very thin both the support and the blood supply of the flap are improved if the dissection is just deep to the orbicularis muscle layer.
There are three basic patterns in the design of skin flaps – advancement, rotation and transposition flaps. These are described later in this chapter. All skin flaps create inherent tension. This is because, unlike skin grafts, no extra tissue is added to the area to allow closure of the primary defect. The transfer of the flap into the primary defect creates a secondary defect which requires closure separately.
In an advancement flap or a rotation flap the secondary defect is ‘virtual’ – the base of the flap is stretched to allow closure of the primary defect without the creation of a true secondary defect. It is made possible by wide undermining of the skin around the flap. The disadvantage of these flaps is that they tend to pull back toward the origin of the flap, creating tension at the site of the primary defect. This demands particular care in their design close to the lid margins. Tension must be strictly horizontal, not vertical, if lid margin distortion is to be avoided.
A transposition flap, by contrast, creates little tension across the primary defect after closure. There is tension, however, in the closure of the secondary defect. The vector of tension is across the line of the secondary defect. This is reduced by adequate local undermining.
Choice of operation
Guidelines for the use of each flap are given with the description of each procedure.
Advancement flaps
15.5
Advancement flap in the cheek ( )
Small defects may be reconstructed simply with an advancement of local skin. The design should ensure that tension through the flap is horizontal, not vertical, in the upper cheek to reduce the risk of distortion of the lid margin.
Close the primary defect in two layers with 4/0 absorbable sutures to the subcutaneous fat layer and with 4/0 or 6/0 sutures to the skin. Close the edges of the flap in the same way. If dog-ears form either side of the base of the flap when it is advanced, they may be excised by carefully cutting around the base of each triangle. Stay within normal skin to avoid compromising the blood supply to the flap.
15.6
Advancement flaps in the lower lid
A simple advancement or sliding flap may be used if the leading edge has to be advanced up to about one-third of the lid to achieve closure of the defect without undue tension. The flaps may be advanced from the temporal side only or, for a central anterior lamellar defect, from medial and lateral sides.
It is important that the line of incision from the lateral canthus is not horizontal but a continuation of the line of the lid to be reconstructed. If this is not done a shallow depression will appear in the lateral part of the reconstructed lid margin.
Ischaemia or necrosis of a broad flap is uncommon but the tip of a narrow advancement flap may be at risk. If it appears dark in the first few postoperative days, wait. More will survive than seems likely initially.
The lateral canthus may drop after use of the narrow flap unless the flap is firmly supported with deep sutures laterally.
Rotation flaps
A rotation flap is a local flap which can be thought of as several clock-hours of a clock face. The primary defect is created by removing a segment of one or more clock-hours (which includes the lesion) and the remaining clock-hours expand to fill the gap.
It can be seen that the defect must be triangular with its apex toward the centre of rotation of the flap. A rotation flap does not create a secondary defect which has to be closed. Tension within the flap may cause distortion of the tissues as the flap tends to pull back toward its origin. The ‘ O to Z ’ flap is a double rotation flap useful for smaller defects. The Mustardé cheek rotation flap is an example of a rotation flap used for large defects, especially those extending from the lower lid into the cheek.
15.7
O to Z rotation flaps
15.8
Mustardé cheek rotation flap
The Mustardé cheek rotation flap is used to reconstruct large defects of the lower lid up to the whole lid length and, in particular, those defects with a large vertical component extending into the cheek. It can also be used for large defects which do not involve the lid margin. By varying the size of the cheek flap smaller defects of the lateral, central or even medial part of the lower lid can be reconstructed with this technique.
Transposition flaps
A transposition flap is a local flap in which skin is raised on a pedicle at one end and transferred to cover a nearby primary defect. In the face the length/breadth ratio may be greater than 1 : 1. A secondary defect is created at the donor site which may be closed directly or with a free skin graft. The flap should be designed so that the vector of tension, which is across the line of closure of the secondary defect, is parallel to the lid margin to avoid distortion. This is less important if there is excess local skin for closure of the secondary defect – for example in the upper lid in an upper to lower lid transposition flap.
The design of transposition flaps is important particularly if thicker cheek or forehead skin is to be used. The fundamental point is that the shorter diagonal (AB, Diag. 15.2 ) before the flap is transposed becomes the longer diagonal (BC) after it is transposed (A to C). Allowance must be made (B to A’), in the design of the flap, for this apparent shortening.
If there is limited elasticity in the flap allowance must also be made for this in designing the flap.
The Mustardé cheek rotation flap is used to reconstruct large defects of the lower lid up to the whole lid length and, in particular, those defects with a large vertical component extending into the cheek. It can also be used for large defects which do not involve the lid margin. By varying the size of the cheek flap smaller defects of the lateral, central or even medial part of the lower lid can be reconstructed with this technique.
Mark the outline of the lesion and the extent of tissue to be excised to remove it. From the medial limit of the tissue to be excised, mark a line vertically downwards beside the nose. It should be approximately twice as long as the horizontal extent of the tissue to be excised. From the end of this line draw a second line upwards and laterally to join the lateral limit of the tissue to be excised to create an inverted triangle. From the lateral canthus mark a line which curves upwards toward the lateral end of the eyebrow. If the whole lid is to be reconstructed continue the line in a gentle curve across the temple skin and down just in front of the ear as far as the ear lobe.
Excise the inverted triangle, including the lesion, staying superficial to the facial muscles unless they are involved with the tumour. Incise the skin to outline the cheek flap. Undermine the tissues within the orbital margin, just deep to the orbicularis muscle as far as the lateral orbital rim. Continue to undermine the cheek flap, dissecting more superficially once the lateral orbital rim has been crossed, within the subcutaneous fat layer, superficial to the orbicularis and the facial musculature. Continue to undermine in this plane until the flap can be rotated to fill the defect without undue tension. A back cut at the lower end of the incision by the ear lobe may help to achieve a comfortable rotation of the flap.
Reconstruct the posterior lamella using buccal mucous membrane, hard palate or nasal septal cartilage with its mucoperichondrium (see 16.2 , 2.15 , 2.18 ). There should be excess mucosa along the superior edge for later reconstruction of the lid margin. If nasal septal cartilage with mucoperichondrium is used, Mustardé recommended that the cartilage should rest on the lower orbital rim to provide support for the reconstructed lid. Suture the posterior graft to the conjunctiva in the fornix with interrupted 6/0 absorbable sutures or a 6/0 monofilament suture which can be pulled out.
Insert a vacuum drain at the lowest point beneath a large flap. Begin the closure of the defect at the new lid margin by fixing the superomedial corner of the flap to the periosteum of the anterior lacrimal crest with 5/0 nonabsorbable sutures. If the defect is smaller and there is tarsal plate medially close the lid in the usual way (see 14.1 , 14.2 ). If there is any residual horizontal laxity pull the lid gently laterally and place a 4/0 nonabsorbable suture from the periosteum, just superior to the insertion of the lateral canthal tendon, to the subcutaneous tissues of the flap to support the flap and stabilise the new lateral canthus. Place four or five deep sutures between the flap and the inferior orbital rim and deep tissues to provide support. An alternative technique to support the lateral end of the reconstructed lower lid is the Hewes flap (see 16.6 ). Close the mucosa to skin at the lid margin with a continuous 6/0 monofilament suture.
Reconstruction of part of the lower eyelid
If less than the whole lower lid is to be reconstructed proceed as described earlier but incise along the edge of the cheek flap only 2 to 3 cm at a time and undermine just that part of the flap. Repeat this stepwise development of the flap until the defect can be closed. This is easiest for lateral defects.
With central or medial lid defects a lateral fragment of lid remains. This must be mobilised and closed directly to the medial lid tissues and the cheek flap rotated to form the lateral part of the reconstructed lid. To mobilise the lateral fragment of lid cut the lower limb of the lateral canthal tendon (see 14.2c ) and free the orbital septum from the inferior orbital rim. To do this, introduce scissors between the conjunctiva and the orbicularis muscle laterally, staying close to the inferior orbital rim. If the defect is in the medial part of the lid the conjunctiva also must be incised in the lateral fornix to mobilise the lateral lid fragment.
If a smaller defect of one-half the lid length or less is being reconstructed no posterior lamellar reconstruction is needed. For defects of more than one-half of the lid length a new lining of mucosa, or a composite graft of nasal mucosa and cartilage, must be inserted as a posterior lining lamella for the lateral part of the lid.
Closure is the same as for the full cheek flap including the deep suture between the subcutaneous tissues and the periosteum of the orbital rim to support the flap.
In the early postoperative period part of the flap may necrose. This is most often a small area of doubtful circulation in the superior medial corner and recovery of all of it is usual. Occasionally a larger area may necrose requiring later grafting after at least 6 weeks.
In the longer term the most common complication is sagging of the lower lid margin. This is minimised by using nasal septal chondromucosa as the lining of the flap or by providing extra support laterally (e.g. with a Hewes flap) (see 16.6 ). Despite a relatively large area of scleral show exposure of the eye is uncommon. The wide, shallow defect in the lid may be reconstructed, but it is often difficult to achieve a completely satisfactory lower lid position. A Hughes’ procedure may be effective.
15.9
Upper lid to lower lid transposition flap – based laterally
This flap is used for defects in the lower lid which extend to the lateral canthus.
Mark the skin crease in the upper lid. This will be the inferior border of the flap. Assess the width of flap needed to cover the defect. Draw a line this distance above the marked skin crease. Extend both lines downwards and laterally into healthy skin to the site of the pedicle which should be positioned to allow transposition of the flap to the lower lid. Assess the length of flap needed, bearing in mind the rules of design previously outlined ( p. 104 , Diag. 15.2 ). If in doubt, check that the flap is long enough by placing a length of suture between the superior end of the pedicle laterally and the inferior, medial corner of the defect in the lid. Knot the suture at this point. Now measure from the same point on the pedicle and note where the knot in the suture crosses the skin crease. This is the end of the flap. Tapering of the incision to allow easier closure of the lid is beyond this point (see also 7.12 ).
Raise the skin flap. Undermine the skin for a short distance around the pedicle to allow transposition of the flap but take care not to damage the blood supply. Suture the flap into the defect with 6/0 or 7/0 sutures. If the superior border of the flap sits securely against the posterior lamella no suture is necessary along the lid margin. If not, place a continuous 6/0 monofilament suture along the new lid margin to unite the skin and mucosa. Quilting sutures may be used to stabilise the flap (see 2.14 and 7.12i,j ).
15.10
Upper lid to lower lid transposition flap – based medially
This flap is used for defects in the lower lid which extend to the medial canthus.
Assess the width and length of flap required to fill the anticipated size of the defect. Mark the upper lid skin crease. This border of the flap will be the lower border of the reconstruction. Mark the upper border of the flap. This will normally create a flap equal to the width of the defect or slightly wider to allow for any drop of the cheek in the upright position, with traction on the lower lid. (See also comment in 15.10b , e .) Place the base of the flap medially so that the inferior border joins the inferior border of the defect and the upper border is just superior to the inner canthus to create a flap slightly wider at its base than elsewhere.
Cut the flap. Orbicularis muscle can be included to help fill a deeper defect. In the case illustrated the defect is deeper vertically than can be filled easily with a flap from the upper lid. An alternative would be a nasojugal flap (see 15.11 ). The flap has been marked longer than is required by the defect so that the excess can be used as a full-thickness graft to fill the inferior part of the defect.
Suture the flap into the defect with 6/0 or 7/0 absorbable sutures. As noted in 15.8c, if the superior border of the flap sits securely against the posterior lamella no suture is necessary along the lid margin. If not, place a continuous 6/0 monofilament suture along the new lid margin to unite the skin and mucosa (see 15.10e ). Use interrupted 6/0 sutures elsewhere.
In this case the end of the upper lid flap (which was cut longer than necessary for the width of the defect) has been trimmed to create two small grafts to fill the inferior part of the defect. Quilting sutures may be used to stabilise the flap (see 2.14 and 7.12g–j )
Upper lid skin is thin so care must be taken to provide adequate support in the posterior lamellar reconstruction.
The tip of the flap may show signs of ischaemia in the immediate postoperative period. More survives than seems likely at first.
15.11
Nasojugal transposition flap
This flap is useful for defects of the medial half of the lower lid but not beyond the medial end of the lid. If the defect extends into the medial canthal area or side wall of the nose the base of the flap will be too anteriorly placed and it will be difficult to achieve close approximation to the globe medially.
Reconstruct the posterior lamella with a suitable graft or a tarsoconjunctival flap (see Ch. 16 ). A tarsal graft was used in the case illustrated. The flap is almost vertical in the nasojugal area with its base just inferior to the medial canthus. Design the flap as described earlier (see ‘Transposed flaps’ Diag. 15.2 ).
As previously noted with other lower lid flaps, if the superior border of the flap sits securely against the posterior lamella no suture is necessary along the lid margin. If not, place a continuous 6/0 monofilament suture along the new lid margin to unite the skin and mucosa. Close the cheek wound first. Transpose the flap into the defect and trim it to fit. Close the skin with interrupted 6/0 sutures.
Nasojugal skin is thicker than eyelid skin and the reconstruction may be rather bulky. Later debulking is possible if necessary.
15.12
Lateral cheek to lower lid transposition flap
Large lower lid defects which extend to the lateral canthus can be reconstructed with a transposed flap based near the outer canthus, extending down into the cheek. This technique can be used for defects up to the full width of the lid, and for relatively shallow defects (15.12a–c) or deeper defects (15.12d–g). Take care to design the flap with sufficient length and width to fill the defect. It must be lined with a suitable posterior graft, for example tarsal plate or oral mucosa. To close the secondary defect, undermine the edges of the wound.
Excise the tumour. Reconstruct the posterior lamella ( Ch. 16 ). Mark the flap on the cheek: the medial edge of the flap is continuous with the lateral edge of the defect. Incise to the depth of the subcutaneous fat layer. Undermine the flap and adjacent skin. The level of dissection for narrower cheek flaps can be more superficial than that for larger flaps. Transpose the flap into the defect to check the fit. If it does not transpose easily, undermine the adjacent cheek further, within the fat layer, until it can be transposed comfortably.
Trim the leading end of the flap to fit the medial edge of the defect in the lid. Suture the flap into place. As noted previously, a suture along the lid margin is needed only if the anterior and posterior lamellae do not sit well together (15.10e). Often the lamellae do not require a suture (15.12g).
Complications and their management are the same as those given for nasojugal flaps.
15.13
Rhombic transposition flap ( )
A rhombus is a parallelogram with oblique angles and equal sides. A defect of this shape constructed around the site of excision of a tumour can be filled with a rhombic flap. This flap is marked on the skin as shown in the Diag. 15.3 . Four possible rhombic flaps can be constructed for any rhombus-shaped defect: the first line in construction of the flap may be from either side of the shorter axis of the rhomboid defect; the second line may be in either direction from this line but parallel to the side of the rhomboid. The direction of the flap chosen depends on the availability of relaxed skin to allow the flap to be transposed into the defect. The vector of maximum tension is through the base of the flap ( Diag. 15.3 ). The choice of flap should place the tension vector parallel to the local relaxed skin tension lines if possible. This reduces scarring and minimises distortion of any nearby lid margin.
Rhombic flaps are useful for reconstruction around the canthi, especially the medial canthus.
Having excised the tumour, assess the suitability of the defect for reconstruction with a rhombic flap. The defect must be approximately containable within an imaginary rhomboid shape. Draw a line as an extension of the shorter axis of the rhombus and equal in length to it. Draw a second line equal in length and parallel to the side of the rhomboid defect, its direction depending on the chosen orientation of the flap.
15.14
Bilobed transposition flap
This flap is used for small to medium sized defects. A primary flap, about 75% of the diameter of the primary defect, is marked. A secondary flap is marked with a diameter of 50% to 60% of the primary flap ( Diag. 15.4 ). It should lie within an area of relatively relaxed skin. The flaps should not be transposed through more than 60 to 70 degrees although up to 90 degrees may be possible if essential. It is particularly useful if there is tight skin around the primary defect but less tight skin nearby that allows the secondary flap to be mobilised and transposed, for example in reconstruction of small defects of the inner canthus. The vector of tension is along the axis of the defect and the two flaps ( Diag. 15.4 ). This line should lie parallel to the relaxed skin tension lines.
Glabellar flaps
A full-thickness skin graft may be used for superficial defects at the inner canthus. If the defect is deep, a glabellar flap is preferred. It does not require a posterior lamellar reconstruction. Small defects, as in the case illustrated, could be reconstructed with a rhombic or bilobed flap (15.13, 15.14). To construct a glabellar flap, an inverted V is created in the glabellar region and converted to a Y to allow the flap to be transferred to the inner canthus. If the defect is small (15.15) the flap is used as a sliding flap, the excess being trimmed off. If the defect is large (15.16) the flap may be used as a transposed flap with little trimming necessary. If the defect extends into the upper or lower eyelid supplementary procedures may be needed to reconstruct the residual lid defect (15.17, 15.18).
15.15
Glabellar V – Y sliding flap
Once the position is satisfactory insert one or two 4/0 nonabsorbable sutures between the deep surface of the flap and the tissues of the canthus to anchor the flap. Undermine either side of the forehead defect to allow closure with minimal tension. Close the forehead in two layers to just above the brows.
Suture the flap into the canthal defect with 6/0 absorbable sutures to the subcutaneous tissues and 6/0 nonabsorbable sutures to the skin. If the triangular gap between the glabellar flap and the forehead is difficult to close, part of the tissue excised from the glabellar flap can be inserted as a graft. Complete the closure of the forehead. Remove all skin sutures at 1 week.
A fold or ‘dog-ear’ commonly occurs on the bridge of the nose, especially if the defect is large. Leave it for 6 weeks and then trim it if necessary. Poor application of the flap to the hollow at the inner canthus, and the appearance of telecanthus, can be avoided by careful placement and suturing of the flap at operation.
15.16
Glabellar transposition flap
In more extensive defects, particularly involving the upper lid, the glabellar flap may be transposed to reserve the apex of the flap for use in the reconstruction.
Having excised the tumour, draw the lids medially to estimate the size of flap required. Mark a large glabellar flap extending further up the forehead but otherwise following the principles previously described (see 15.14a ).
Close the forehead in two layers to just above the brows. Transpose the whole flap into the defect. When a satisfactory position is achieved place one or two deep nonabsorbable 4/0 sutures between the deep surface of the flap and the inner canthal tissues to anchor the flap at the canthus. The lids may be closed with a temporary tarsorrhaphy suture if this helps the orientation of the flap.
Complications and their management are the same as those described for the glabellar sliding flap (see 15.15 ).
15.17
Glabellar flap and Cutler-Beard bridge flap combined
This combination of flaps is useful in the reconstruction of large defects in the upper lid which include a deep defect above the medial canthal tendon. Having excised the tumour adequately assess whether a glabellar flap alone will be sufficient for reconstruction. If not, plan the glabellar flap first.
Complete the glabellar flap (see 15.15f ) and then suture the bridge flap into the residual defect in the upper lid.
15.18
Glabellar flap and Hughes’ tarsoconjunctival flap combined
This combination of procedures is useful for large defects of the lower lid which include the inner canthus.